Multiattack

The oozasis makes two pseudopod attacks.

Pseudopod

Melee Weapon Attack: +8 to hit, reach 15 ft., one creature. Hit: 13 (2d8 + 4) bludgeoning damage plus 10 (3d6) acid damage, and a target that's Large or smaller is grappled (escape DC 16) and restrained until the grapple ends. The oozasis has two pseudopods, each of which can grapple one target at a time.

Engulf

The oozasis engulfs creatures grappled by it. An engulfed creature can't breathe, is restrained, is no longer grappled, has total cover against attacks and other effects outside the oozasis, takes 21 (6d6) acid damage at the start of each of the oozasis's turns, and is subject to the oozasis's Waters of Unfathomable Compulsion trait. The creature takes no damage if the oozasis chooses not to inflict any. When the oozasis moves, the engulfed creature moves with it. An engulfed creature can escape by using an action and making a successful DC 16 Strength check. On a success, the creature enters a space of its choice within 5 feet of the oozasis.

Vapors of Tranquility or Turmoil (Recharges after a Short or Long Rest)

The oozasis sublimates its waters into a vapor that fills a disk centered on the oozasis, 60 feet in radius, and 10 feet thick. All creatures in the area are affected by either the calm emotions spell or the confusion spell (save DC 16). The oozasis chooses which effect to use, and it must be the same for all creatures.